A ground anchor system is designed to support a structure (e.g., ground) and is typically used in geotechnical applications. Ground anchor systems consisting of tendons (e.g., cables or rods) connected to a bearing plate are often used for the stabilization of steep slopes or slopes consisting of softer soils, as well as the enhancement of embankment or foundation soil capacity, or to prevent excessive erosion and landslides. Ground anchor systems can hold the walls and posts of outdoor structures to the ground without a foundation or concrete-filled post holes. The strength of the ground anchor's grip is largely determined by the consistency of the site's soil.
Ground anchor systems can be used in either temporary or permanent applications. Typical use for ground anchor systems includes supporting retaining walls.
Although most typically made of metallic materials, the tendons of ground anchor systems can be made of fiber reinforced polymer (FRP), and can have a flat and an elongated shape. FRP is a composite material made of a polymer matrix reinforced with fibers. The fibers are usually glass, carbon, basalt or aramid, although other fibers such as paper or wood or asbestos are sometimes used.
In particular, it is appreciated that the tendons of ground anchor systems can be made of carbon-fiber-reinforced polymer, carbon-fiber-reinforced plastic or carbon-fiber-reinforced thermoplastic (CFRP, CRP, CFRTP or often simply carbon fiber, or even carbon), which are extremely strong and light fiber-reinforced polymers which contain carbon fibers.
CFRP straps are characterized by light weight, corrosion resistant, and can be easily trimmed or cut if required. Due to these characteristics, CFRP are highly suitable for offshore environments and crowded construction areas.
An example for a ground anchor system can be found in EP 726383, which discloses a device for reinforcement, consolidation and stabilization of the ground, particularly for preventing landslides or deformation of the working face in tunnels or trenches, comprising an injection tube, advantageously with valves, to be inserted in a respective borehole in the ground, around which tube are arranged a plurality of strong reinforcing elements, mounted by means of centering spacers and held together by external retaining elements. According to a particular example disclosed in EP 726383, the tendons are made of glass fiber bars, composed by parallel and continuous glass fibers embedded in a polymer matrix. The use of this material has recently become wide in the field of geotechnical and civil engineering, due to its characteristics. These characteristics include, for example, high tensile strength (twice that of standard steel), corrosion resistance, lightweight, thermal insulation, magnetic insulation and electric insulation.